Unlike EAServer 5.x, you must set a valid password for EASever 6.1, otherwise EAServer 6.1 cannot started.
You can follow the folloing steps to set password for EAServer 6.1
Step 1: Run the following command in a prompt window. (%EAServer% stands for the installation path of EAServer. )
%EAServer%\bin set-admin-password.bat
Step 2: Input a password that has at least six characters combining both letters and numbers.
Step 3: Mask sure you get following message saying that the password is set seccessfully.